```html
<!DOCTYPE html>
<html lang="zh-CN">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>SVGtoPNG - 高品质矢量图形转换工具</title>
    <link rel="stylesheet" href="https://cdn.staticfile.org/font-awesome/6.4.0/css/all.min.css">
    <link rel="stylesheet" href="https://cdn.staticfile.org/tailwindcss/2.2.19/tailwind.min.css">
    <link href="https://fonts.googleapis.com/css2?family=Noto+Serif+SC:wght@400;500;600;700&family=Noto+Sans+SC:wght@300;400;500;700&display=swap" rel="stylesheet">
    <script src="https://cdn.jsdelivr.net/npm/mermaid@latest/dist/mermaid.min.js"></script>
    <style>
        body {
            font-family: 'Noto Sans SC', Tahoma, Arial, Roboto, "Droid Sans", "Helvetica Neue", "Droid Sans Fallback", "Heiti SC", "Hiragino Sans GB", Simsun, sans-serif;
            background-color: #f8fafc;
            color: #1e293b;
        }
        .hero-gradient {
            background: linear-gradient(135deg, #6366f1 0%, #8b5cf6 50%, #d946ef 100%);
        }
        .feature-card:hover {
            transform: translateY(-5px);
            box-shadow: 0 20px 25px -5px rgba(0, 0, 0, 0.1), 0 10px 10px -5px rgba(0, 0, 0, 0.04);
        }
        .tooltip:hover .tooltip-text {
            visibility: visible;
            opacity: 1;
        }
        .concept-icon {
            transition: all 0.3s ease;
        }
        .concept-icon:hover {
            transform: scale(1.1);
        }
        .dropzone {
            border: 2px dashed #cbd5e1;
            transition: all 0.3s ease;
        }
        .dropzone-active {
            border-color: #6366f1;
            background-color: #eef2ff;
        }
        .btn-primary {
            background-color: #6366f1;
            transition: all 0.3s ease;
        }
        .btn-primary:hover {
            background-color: #4f46e5;
            transform: translateY(-2px);
        }
        .btn-secondary {
            background-color: #f1f5f9;
            transition: all 0.3s ease;
        }
        .btn-secondary:hover {
            background-color: #e2e8f0;
            transform: translateY(-2px);
        }
        .highlight {
            position: relative;
            z-index: 1;
        }
        .highlight:after {
            content: '';
            position: absolute;
            bottom: 0;
            left: 0;
            width: 100%;
            height: 30%;
            background-color: rgba(99, 102, 241, 0.2);
            z-index: -1;
            transition: all 0.3s ease;
        }
        .highlight:hover:after {
            height: 50%;
        }
    </style>
</head>
<body>
    <!-- Hero Section -->
    <section class="hero-gradient text-white py-20 px-4 md:px-0">
        <div class="container mx-auto max-w-6xl flex flex-col md:flex-row items-center">
            <div class="md:w-1/2 mb-10 md:mb-0 md:pr-10">
                <h1 class="text-4xl md:text-5xl font-bold mb-6 leading-tight font-serif">矢量图形转换<br><span class="highlight">瞬间完成</span></h1>
                <p class="text-xl mb-8 opacity-90 leading-relaxed">SVGtoPNG 是设计师与开发者的首选工具，将矢量图形无损转换为高质量 PNG，保持完美清晰度。</p>
                <div class="flex flex-wrap gap-4">
                    <button class="btn-primary text-white px-8 py-3 rounded-lg font-medium shadow-lg flex items-center">
                        <i class="fas fa-upload mr-2"></i>立即转换
                    </button>
                    <button class="btn-secondary text-slate-700 px-8 py-3 rounded-lg font-medium shadow-lg flex items-center">
                        <i class="fas fa-play-circle mr-2"></i>观看演示
                    </button>
                </div>
            </div>
            <div class="md:w-1/2 relative">
                <div class="bg-white bg-opacity-20 backdrop-filter backdrop-blur-lg rounded-xl p-6 shadow-2xl">
                    <div class="dropzone rounded-lg p-8 text-center cursor-pointer">
                        <i class="fas fa-cloud-upload-alt text-4xl text-white mb-4 opacity-80"></i>
                        <h3 class="text-xl font-semibold mb-2">拖放SVG文件到此处</h3>
                        <p class="text-white text-opacity-80 mb-4">或点击上传</p>
                        <div class="inline-block bg-white bg-opacity-30 text-white px-4 py-2 rounded-md">选择文件</div>
                    </div>
                </div>
                <div class="absolute -bottom-6 -right-6 bg-indigo-100 rounded-full w-32 h-32 opacity-20"></div>
                <div class="absolute -top-6 -left-6 bg-pink-100 rounded-full w-24 h-24 opacity-20"></div>
            </div>
        </div>
    </section>

    <!-- Features Section -->
    <section class="py-20 px-4">
        <div class="container mx-auto max-w-6xl">
            <h2 class="text-3xl font-bold text-center mb-16 font-serif relative">
                <span class="relative inline-block">
                    为什么选择 SVGtoPNG?
                    <span class="absolute bottom-0 left-0 w-full h-1 bg-indigo-200"></span>
                </span>
            </h2>
            
            <div class="grid md:grid-cols-3 gap-8">
                <!-- Feature 1 -->
                <div class="feature-card bg-white rounded-xl p-8 shadow-lg transition-all duration-300">
                    <div class="text-indigo-500 mb-6">
                        <i class="fas fa-bolt text-4xl"></i>
                    </div>
                    <h3 class="text-xl font-bold mb-3">闪电般快速</h3>
                    <p class="text-slate-600">使用先进算法，在几秒钟内完成转换，无需漫长等待。</p>
                </div>
                
                <!-- Feature 2 -->
                <div class="feature-card bg-white rounded-xl p-8 shadow-lg transition-all duration-300">
                    <div class="text-pink-500 mb-6">
                        <i class="fas fa-ruler-combined text-4xl"></i>
                    </div>
                    <h3 class="text-xl font-bold mb-3">精准尺寸控制</h3>
                    <p class="text-slate-600">从16x16到4096x4096像素，满足各种场景需求。</p>
                </div>
                
                <!-- Feature 3 -->
                <div class="feature-card bg-white rounded-xl p-8 shadow-lg transition-all duration-300">
                    <div class="text-purple-500 mb-6">
                        <i class="fas fa-layer-group text-4xl"></i>
                    </div>
                    <h3 class="text-xl font-bold mb-3">透明背景保留</h3>
                    <p class="text-slate-600">完美处理SVG的Alpha通道，输出干净的PNG图像。</p>
                </div>
            </div>
        </div>
    </section>

    <!-- How It Works -->
    <section class="py-20 px-4 bg-slate-50">
        <div class="container mx-auto max-w-6xl">
            <h2 class="text-3xl font-bold text-center mb-16 font-serif">三步完成转换</h2>
            
            <div class="flex flex-col md:flex-row items-center justify-between mb-12">
                <div class="relative md:w-1/3 mb-10 md:mb-0 text-center">
                    <div class="absolute -top-8 -left-8 w-16 h-16 bg-indigo-100 rounded-full z-0 opacity-60"></div>
                    <div class="relative z-10">
                        <div class="w-20 h-20 bg-indigo-500 text-white rounded-full flex items-center justify-center mx-auto mb-4">
                            <span class="text-2xl font-bold">1</span>
                        </div>
                        <h3 class="text-xl font-semibold mb-2">上传SVG文件</h3>
                        <p class="text-slate-600">拖放或点击上传您的矢量图形文件</p>
                    </div>
                </div>
                
                <div class="relative md:w-1/3 mb-10 md:mb-0 text-center">
                    <div class="absolute -top-8 -right-8 w-16 h-16 bg-pink-100 rounded-full z-0 opacity-60"></div>
                    <div class="relative z-10">
                        <div class="w-20 h-20 bg-pink-500 text-white rounded-full flex items-center justify-center mx-auto mb-4">
                            <span class="text-2xl font-bold">2</span>
                        </div>
                        <h3 class="text-xl font-semibold mb-2">设置参数</h3>
                        <p class="text-slate-600">选择输出尺寸、DPI等选项</p>
                    </div>
                </div>
                
                <div class="relative md:w-1/3 text-center">
                    <div class="absolute -bottom-8 -left-8 w-16 h-16 bg-purple-100 rounded-full z-0 opacity-60"></div>
                    <div class="relative z-10">
                        <div class="w-20 h-20 bg-purple-500 text-white rounded-full flex items-center justify-center mx-auto mb-4">
                            <span class="text-2xl font-bold">3</span>
                        </div>
                        <h3 class="text-xl font-semibold mb-2">下载PNG</h3>
                        <p class="text-slate-600">获取您的高质量PNG文件</p>
                    </div>
                </div>
            </div>
            
            <div class="text-center">
                <button class="btn-primary text-white px-8 py-3 rounded-lg font-medium shadow-lg mx-auto flex items-center">
                    <i class="fas fa-play mr-2"></i>观看视频教程
                </button>
            </div>
        </div>
    </section>

    <!-- Use Cases -->
    <section class="py-20 px-4">
        <div class="container mx-auto max-w-6xl">
            <h2 class="text-3xl font-bold text-center mb-16 font-serif">应用场景</h2>
            
            <div class="grid md:grid-cols-2 gap-8">
                <div class="bg-white rounded-xl overflow-hidden shadow-lg">
                    <div class="h-48 bg-indigo-100 flex items-center justify-center">
                        <i class="fas fa-laptop-code text-6xl text-indigo-500"></i>
                    </div>
                    <div class="p-8">
                        <h3 class="text-xl font-bold mb-3">网页开发</h3>
                        <p class="text-slate-600 mb-4">将矢量图标转换为多尺寸PNG，完美适配各种响应式布局需求。</p>
                        <div class="flex flex-wrap gap-2">
                            <span class="bg-indigo-100 text-indigo-800 px-3 py-1 rounded-full text-sm">favicon</span>
                            <span class="bg-indigo-100 text-indigo-800 px-3 py-1 rounded-full text-sm">Retina显示</span>
                            <span class="bg-indigo-100 text-indigo-800 px-3 py-1 rounded-full text-sm">多设备适配</span>
                        </div>
                    </div>
                </div>
                
                <div class="bg-white rounded-xl overflow-hidden shadow-lg">
                    <div class="h-48 bg-pink-100 flex items-center justify-center">
                        <i class="fas fa-print text-6xl text-pink-500"></i>
                    </div>
                    <div class="p-8">
                        <h3 class="text-xl font-bold mb-3">印刷物料</h3>
                        <p class="text-slate-600 mb-4">生成300DPI的高清印刷用图，确保输出品质无损失。</p>
                        <div class="flex flex-wrap gap-2">
                            <span class="bg-pink-100 text-pink-800 px-3 py-1 rounded-full text-sm">宣传册</span>
                            <span class="bg-pink-100 text-pink-800 px-3 py-1 rounded-full text-sm">海报</span>
                            <span class="bg-pink-100 text-pink-800 px-3 py-1 rounded-full text-sm">名片</span>
                        </div>
                    </div>
                </div>
            </div>
        </div>
    </section>

    <!-- Technical Details -->
    <section class="py-20 px-4 bg-slate-50">
        <div class="container mx-auto max-w-6xl">
            <h2 class="text-3xl font-bold text-center mb-16 font-serif">技术规格</h2>
            
            <div class="flex flex-col md:flex-row gap-8">
                <div class="md:w-1/2">
                    <h3 class="text-xl font-semibold mb-6 relative pl-4">
                        <span class="absolute left-0 top-1/2 transform -translate-y-1/2 w-2 h-2 bg-indigo-500 rounded-full"></span>
                        支持特性
                    </h3>
                    <ul class="space-y-4">
                        <li class="flex items-start">
                            <i class="fas fa-check-circle text-green-500 mt-1 mr-3"></i>
                            <span>所有基本SVG形状和路径</span>
                        </li>
                        <li class="flex items-start">
                            <i class="fas fa-check-circle text-green-500 mt-1 mr-3"></i>
                            <span>文本元素和字体嵌入</span>
                        </li>
                        <li class="flex items-start">
                            <i class="fas fa-check-circle text-green-500 mt-1 mr-3"></i>
                            <span>线性渐变和径向渐变</span>
                        </li>
                        <li class="flex items-start">
                            <i class="fas fa-check-circle text-green-500 mt-1 mr-3"></i>
                            <span>透明度和混合模式</span>
                        </li>
                    </ul>
                </div>
                
                <div class="md:w-1/2">
                    <h3 class="text-xl font-semibold mb-6 relative pl-4">
                        <span class="absolute left-0 top-1/2 transform -translate-y-1/2 w-2 h-2 bg-pink-500 rounded-full"></span>
                        注意事项
                    </h3>
                    <ul class="space-y-4">
                        <li class="flex items-start">
                            <i class="fas fa-exclamation-triangle text-yellow-500 mt-1 mr-3"></i>
                            <span>不支持SVG渐变网格</span>
                        </li>
                        <li class="flex items-start">
                            <i class="fas fa-exclamation-triangle text-yellow-500 mt-1 mr-3"></i>
                            <span>复杂滤镜效果可能渲染不完美</span>
                        </li>
                        <li class="flex items-start">
                            <i class="fas fa-exclamation-triangle text-yellow-500 mt-1 mr-3"></i>
                            <span>超大文件(>10MB)需要付费版</span>
                        </li>
                        <li class="flex items-start">
                            <i class="fas fa-info-circle text-blue-500 mt-1 mr-3"></i>
                            <span>建议使用AI导出的SVG以获得最佳效果</span>
                        </li>
                    </ul>
                </div>
            </div>
        </div>
    </section>

    <!-- API Section -->
    <section class="py-20 px-4 bg-indigo-900 text-white">
        <div class="container mx-auto max-w-6xl">
            <div class="flex flex-col md:flex-row items-center">
                <div class="md:w-1/2 mb-10 md:mb-0">
                    <h2 class="text-3xl font-bold mb-6 font-serif">开发者API</h2>
                    <p class="text-indigo-200 mb-8 leading-relaxed">通过我们的REST API将SVG转换功能集成到您的工作流程中，支持批量处理和自定义参数。</p>
                    
                    <div class="bg-indigo-800 bg-opacity-50 rounded-lg p-6 mb-8">
                        <div class="flex items-center mb-4">
                            <div class="bg-indigo-700 rounded-full w-10 h-10 flex items-center justify-center mr-3">
                                <i class="fas fa-code"></i>
                            </div>
                            <div>
                                <h4 class="font-semibold">API端点</h4>
                                <p class="text-sm text-indigo-300">https://api.svgtopng.com/v1/convert</p>
                            </div>
                        </div>
                        
                        <div class="border-t border-indigo-700 pt-4">
                            <div class="mb-3">
                                <span class="inline-block bg-indigo-600 text-xs px-2 py-1 rounded mr-2">POST</span>
                                <span class="text-indigo-300 text-sm">JSON格式请求</span>
                            </div>
                            <pre class="bg-black bg-opacity-30 p-3 rounded text-sm overflow-x-auto"><code>{
  "svg": "base64编码的SVG内容",
  "width": 512,
  "height": 512,
  "dpi": 72
}</code></pre>
                        </div>
                    </div>
                    
                    <button class="btn-secondary bg-white text-indigo-800 px-6 py-2 rounded-lg font-medium flex items-center">
                        <i class="fas fa-file-alt mr-2"></i>查看完整文档
                    </button>
                </div>
                
                <div class="md:w-1/2 md:pl-10">
                    <div class="bg-white bg-opacity-10 backdrop-filter backdrop-blur-lg rounded-xl p-6">
                        <h3 class="text-xl font-semibold mb-4">API优势</h3>
                        
                        <div class="space-y-4">
                            <div class="flex items-start">
                                <div class="bg-indigo-500 rounded-full w-6 h-6 flex items-center justify-center flex-shrink-0 mr-3 mt-1">
                                    <i class="fas fa-check text-xs"></i>
                                </div>
                                <div>
                                    <h4 class="font-medium">批量处理</h4>
                                    <p class="text-indigo-200 text-sm">一次调用最多支持20个文件同时转换</p>
                                </div>
                            </div>
                            
                            <div class="flex items-start">
                                <div class="bg-indigo-500 rounded-full w-6 h-6 flex items-center justify-center flex-shrink-0 mr-3 mt-1">
                                    <i class="fas fa-check text-xs"></i>
                                </div>
                                <div>
                                    <h4 class="font-medium">CDN加速</h4>
                                    <p class="text-indigo-200 text-sm">转换结果自动分配全球CDN加速链接</p>
                                </div>
                            </div>
                            
                            <div class="flex items-start">
                                <div class="bg-indigo-500 rounded-full w-6 h-6 flex items-center justify-center flex-shrink-0 mr-3 mt-1">
                                    <i class="fas fa-check text-xs"></i>
                                </div>
                                <div>
                                    <h4 class="font-medium">回调通知</h4>
                                    <p class="text-indigo-200 text-sm">转换完成后发送回调通知到指定URL</p>
                                </div>
                            </div>
                            
                            <div class="flex items-start">
                                <div class="bg-indigo-500 rounded-full w-6 h-6 flex items-center justify-center flex-shrink-0 mr-3 mt-1">
                                    <i class="fas fa-check text-xs"></i>
                                </div>
                                <div>
                                    <h4 class="font-medium">状态查询</h4>
                                    <p class="text-indigo-200 text-sm">实时查询转换任务状态和进度</p>
                                </div>
                            </div>
                        </div>
                    </div>
                </div>
            </div>
        </div>
    </section>

    <!-- DPI Explanation -->
    <section class="py-20 px-4">
        <div class="container mx-auto max-w-6xl">
            <div class="flex flex-col md:flex-row items-center">
                <div class="md:w-1/2 mb-10 md:mb-0 md:pr-10">
                    <div class="mermaid">
                        graph TD
                            A[屏幕显示] -->|72-96 DPI| B[网页/移动端]
                            A -->|150-300 DPI| C[高清印刷品]
                            A -->|600+ DPI| D[专业印刷]
                    </div>
                </div>
                
                <div class="md:w-1/2">
                    <h2 class="text-3xl font-bold mb-6 font-serif">关于DPI的选择</h2>
                    <p class="text-slate-600 mb-6 leading-relaxed">DPI(每英寸点数)决定了图像的打印质量。更高的DPI意味着更精细的打印效果，但也会增加文件大小。</p>
                    
                    <div class="space-y-4">
                        <div class="flex items-start">
                            <div class="bg-indigo-100 rounded-full w-8 h-8 flex items-center justify-center flex-shrink-0 mr-3">
                                <span class="text-indigo-800 font-bold">1</span>
                            </div>
                            <div>
                                <h4 class="font-semibold mb-1">屏幕使用 (72-96 DPI)</h4>
                                <p class="text-slate-500 text-sm">适用于网页、APP和电子显示设备</p>
                            </div>
                        </div>
                        
                        <div class="flex items-start">
                            <div class="bg-pink-100 rounded-full w-8 h-8 flex items-center justify-center flex-shrink-0 mr-3">
                                <span class="text-pink-800 font-bold">2</span>
                            </div>
                            <div>
                                <h4 class="font-semibold mb-1">普通打印 (150-300 DPI)</h4>
                                <p class="text-slate-500 text-sm">适合传单、海报和商业印刷品</p>
                            </div>
                        </div>
                        
                        <div class="flex items-start">
                            <div class="bg-purple-100 rounded-full w-8 h-8 flex items-center justify-center flex-shrink-0 mr-3">
                                <span class="text-purple-800 font-bold">3</span>
                            </div>
                            <div>
                                <h4 class="font-semibold mb-1">高端印刷 (600+ DPI)</h4>
                                <p class="text-slate-500 text-sm">用于杂志、画册等高质量印刷需求</p>
                            </div>
                        </div>
                    </div>
                </div>
            </div>
        </div>
    </section>

    <!-- CTA Section -->
    <section class="py-20 px-4 bg-gradient-to-r from-indigo-500 to-purple-600 text-white">
        <div class="container mx-auto max-w-4xl text-center">
            <h2 class="text-3xl font-bold mb-6 font-serif">立即体验高品质SVG转换</h2>
            <p class="text-xl mb-10 opacity-90 leading-relaxed">无需注册，完全免费，开始您的第一个转换任务</p>
            
            <div class="flex flex-col sm:flex-row justify-center gap-4">
                <button class="btn-primary bg-white text-indigo-600 px-8 py-4 rounded-lg font-bold shadow-lg text-lg flex items-center mx-auto sm:mx-0">
                    <i class="fas fa-upload mr-3"></i>上传SVG文件
                </button>
                <button class="btn-secondary bg-indigo-800 bg-opacity-50 text-white px-8 py-4 rounded-lg font-bold shadow-lg text-lg flex items-center mx-auto sm:mx-0">
                    <i class="fas fa-question-circle mr-3"></i>需要帮助?
                </button>
            </div>
        </div>
    </section>

    <script>
        mermaid.initialize({
            startOnLoad: true,
            theme: 'default',
            flowchart: {
                useMaxWidth: true,
                htmlLabels: true,
                curve: 'basis'
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        // Dropzone interaction
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            dropzone.classList.add('dropzone-active');
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        dropzone.addEventListener('dragleave', () => {
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        dropzone.addEventListener('drop', (e) => {
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        // Button hover effects
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</body>
</html>
```